net/mac80211/status.c

   1 /*
   2  * Copyright 2002-2005, Instant802 Networks, Inc.
   3  * Copyright 2005-2006, Devicescape Software, Inc.
   4  * Copyright 2006-2007  Jiri Benc <[email protected]>
   5  * Copyright 2008-2010  Johannes Berg <[email protected]>
   6  * Copyright 2013-2014  Intel Mobile Communications GmbH
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 #include <linux/export.h>
  14 #include <linux/etherdevice.h>
  15 #include <linux/time.h>
  16 #include <net/mac80211.h>
  17 #include <asm/unaligned.h>
  18 #include "ieee80211_i.h"
  19 #include "rate.h"
  20 #include "mesh.h"
  21 #include "led.h"
  22 #include "wme.h"
  23
  24
  25 void ieee80211_tx_status_irqsafe(struct ieee80211_hw *hw,
  26                                  struct sk_buff *skb)
  27 {
  28         struct ieee80211_local *local = hw_to_local(hw);
  29         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
  30         int tmp;
  31
  32         skb->pkt_type = IEEE80211_TX_STATUS_MSG;
  33         skb_queue_tail(info->flags & IEEE80211_TX_CTL_REQ_TX_STATUS ?
  34                        &local->skb_queue : &local->skb_queue_unreliable, skb);
  35         tmp = skb_queue_len(&local->skb_queue) +
  36                 skb_queue_len(&local->skb_queue_unreliable);
  37         while (tmp > IEEE80211_IRQSAFE_QUEUE_LIMIT &&
  38                (skb = skb_dequeue(&local->skb_queue_unreliable))) {
  39                 ieee80211_free_txskb(hw, skb);
  40                 tmp--;
  41                 I802_DEBUG_INC(local->tx_status_drop);
  42         }
  43         tasklet_schedule(&local->tasklet);
  44 }
  45 EXPORT_SYMBOL(ieee80211_tx_status_irqsafe);
  46
  47 static void ieee80211_handle_filtered_frame(struct ieee80211_local *local,
  48                                             struct sta_info *sta,
  49                                             struct sk_buff *skb)
  50 {
  51         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
  52         struct ieee80211_hdr *hdr = (void *)skb->data;
  53         int ac;
  54
  55         /*
  56          * This skb 'survived' a round-trip through the driver, and
  57          * hopefully the driver didn't mangle it too badly. However,
  58          * we can definitely not rely on the control information
  59          * being correct. Clear it so we don't get junk there, and
  60          * indicate that it needs new processing, but must not be
  61          * modified/encrypted again.
  62          */
  63         memset(&info->control, 0, sizeof(info->control));
  64
  65         info->control.jiffies = jiffies;
  66         info->control.vif = &sta->sdata->vif;
  67         info->flags |= IEEE80211_TX_INTFL_NEED_TXPROCESSING |
  68                        IEEE80211_TX_INTFL_RETRANSMISSION;
  69         info->flags &= ~IEEE80211_TX_TEMPORARY_FLAGS;
  70
  71         sta->tx_filtered_count++;
  72
  73         /*
  74          * Clear more-data bit on filtered frames, it might be set
  75          * but later frames might time out so it might have to be
  76          * clear again ... It's all rather unlikely (this frame
  77          * should time out first, right?) but let's not confuse
  78          * peers unnecessarily.
  79          */
  80         if (hdr->frame_control & cpu_to_le16(IEEE80211_FCTL_MOREDATA))
  81                 hdr->frame_control &= ~cpu_to_le16(IEEE80211_FCTL_MOREDATA);
  82
  83         if (ieee80211_is_data_qos(hdr->frame_control)) {
  84                 u8 *p = ieee80211_get_qos_ctl(hdr);
  85                 int tid = *p & IEEE80211_QOS_CTL_TID_MASK;
  86
  87                 /*
  88                  * Clear EOSP if set, this could happen e.g.
  89                  * if an absence period (us being a P2P GO)
  90                  * shortens the SP.
  91                  */
  92                 if (*p & IEEE80211_QOS_CTL_EOSP)
  93                         *p &= ~IEEE80211_QOS_CTL_EOSP;
  94                 ac = ieee802_1d_to_ac[tid & 7];
  95         } else {
  96                 ac = IEEE80211_AC_BE;
  97         }
  98
  99         /*
 100          * Clear the TX filter mask for this STA when sending the next
 101          * packet. If the STA went to power save mode, this will happen
 102          * when it wakes up for the next time.
 103          */
 104         set_sta_flag(sta, WLAN_STA_CLEAR_PS_FILT);
 105
 106         /*
 107          * This code races in the following way:
 108          *
 109          *  (1) STA sends frame indicating it will go to sleep and does so
 110          *  (2) hardware/firmware adds STA to filter list, passes frame up
 111          *  (3) hardware/firmware processes TX fifo and suppresses a frame
 112          *  (4) we get TX status before having processed the frame and
 113          *      knowing that the STA has gone to sleep.
 114          *
 115          * This is actually quite unlikely even when both those events are
 116          * processed from interrupts coming in quickly after one another or
 117          * even at the same time because we queue both TX status events and
 118          * RX frames to be processed by a tasklet and process them in the
 119          * same order that they were received or TX status last. Hence, there
 120          * is no race as long as the frame RX is processed before the next TX
 121          * status, which drivers can ensure, see below.
 122          *
 123          * Note that this can only happen if the hardware or firmware can
 124          * actually add STAs to the filter list, if this is done by the
 125          * driver in response to set_tim() (which will only reduce the race
 126          * this whole filtering tries to solve, not completely solve it)
 127          * this situation cannot happen.
 128          *
 129          * To completely solve this race drivers need to make sure that they
 130          *  (a) don't mix the irq-safe/not irq-safe TX status/RX processing
 131          *      functions and
 132          *  (b) always process RX events before TX status events if ordering
 133          *      can be unknown, for example with different interrupt status
 134          *      bits.
 135          *  (c) if PS mode transitions are manual (i.e. the flag
 136          *      %IEEE80211_HW_AP_LINK_PS is set), always process PS state
 137          *      changes before calling TX status events if ordering can be
 138          *      unknown.
 139          */
 140         if (test_sta_flag(sta, WLAN_STA_PS_STA) &&
 141             skb_queue_len(&sta->tx_filtered[ac]) < STA_MAX_TX_BUFFER) {
 142                 skb_queue_tail(&sta->tx_filtered[ac], skb);
 143                 sta_info_recalc_tim(sta);
 144
 145                 if (!timer_pending(&local->sta_cleanup))
 146                         mod_timer(&local->sta_cleanup,
 147                                   round_jiffies(jiffies +
 148                                                 STA_INFO_CLEANUP_INTERVAL));
 149                 return;
 150         }
 151
 152         if (!test_sta_flag(sta, WLAN_STA_PS_STA) &&
 153             !(info->flags & IEEE80211_TX_INTFL_RETRIED)) {
 154                 /* Software retry the packet once */
 155                 info->flags |= IEEE80211_TX_INTFL_RETRIED;
 156                 ieee80211_add_pending_skb(local, skb);
 157                 return;
 158         }
 159
 160         ps_dbg_ratelimited(sta->sdata,
 161                            "dropped TX filtered frame, queue_len=%d PS=%d @%lu\n",
 162                            skb_queue_len(&sta->tx_filtered[ac]),
 163                            !!test_sta_flag(sta, WLAN_STA_PS_STA), jiffies);
 164         ieee80211_free_txskb(&local->hw, skb);
 165 }
 166
 167 static void ieee80211_check_pending_bar(struct sta_info *sta, u8 *addr, u8 tid)
 168 {
 169         struct tid_ampdu_tx *tid_tx;
 170
 171         tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
 172         if (!tid_tx || !tid_tx->bar_pending)
 173                 return;
 174
 175         tid_tx->bar_pending = false;
 176         ieee80211_send_bar(&sta->sdata->vif, addr, tid, tid_tx->failed_bar_ssn);
 177 }
 178
 179 static void ieee80211_frame_acked(struct sta_info *sta, struct sk_buff *skb)
 180 {
 181         struct ieee80211_mgmt *mgmt = (void *) skb->data;
 182         struct ieee80211_local *local = sta->local;
 183         struct ieee80211_sub_if_data *sdata = sta->sdata;
 184
 185         if (local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS)
 186                 sta->last_rx = jiffies;
 187
 188         if (ieee80211_is_data_qos(mgmt->frame_control)) {
 189                 struct ieee80211_hdr *hdr = (void *) skb->data;
 190                 u8 *qc = ieee80211_get_qos_ctl(hdr);
 191                 u16 tid = qc[0] & 0xf;
 192
 193                 ieee80211_check_pending_bar(sta, hdr->addr1, tid);
 194         }
 195
 196         if (ieee80211_is_action(mgmt->frame_control) &&
 197             mgmt->u.action.category == WLAN_CATEGORY_HT &&
 198             mgmt->u.action.u.ht_smps.action == WLAN_HT_ACTION_SMPS &&
 199             ieee80211_sdata_running(sdata)) {
 200                 enum ieee80211_smps_mode smps_mode;
 201
 202                 switch (mgmt->u.action.u.ht_smps.smps_control) {
 203                 case WLAN_HT_SMPS_CONTROL_DYNAMIC:
 204                         smps_mode = IEEE80211_SMPS_DYNAMIC;
 205                         break;
 206                 case WLAN_HT_SMPS_CONTROL_STATIC:
 207                         smps_mode = IEEE80211_SMPS_STATIC;
 208                         break;
 209                 case WLAN_HT_SMPS_CONTROL_DISABLED:
 210                 default: /* shouldn't happen since we don't send that */
 211                         smps_mode = IEEE80211_SMPS_OFF;
 212                         break;
 213                 }
 214
 215                 if (sdata->vif.type == NL80211_IFTYPE_STATION) {
 216                         /*
 217                          * This update looks racy, but isn't -- if we come
 218                          * here we've definitely got a station that we're
 219                          * talking to, and on a managed interface that can
 220                          * only be the AP. And the only other place updating
 221                          * this variable in managed mode is before association.
 222                          */
 223                         sdata->smps_mode = smps_mode;
 224                         ieee80211_queue_work(&local->hw, &sdata->recalc_smps);
 225                 } else if (sdata->vif.type == NL80211_IFTYPE_AP ||
 226                            sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
 227                         sta->known_smps_mode = smps_mode;
 228                 }
 229         }
 230 }
 231
 232 static void ieee80211_set_bar_pending(struct sta_info *sta, u8 tid, u16 ssn)
 233 {
 234         struct tid_ampdu_tx *tid_tx;
 235
 236         tid_tx = rcu_dereference(sta->ampdu_mlme.tid_tx[tid]);
 237         if (!tid_tx)
 238                 return;
 239
 240         tid_tx->failed_bar_ssn = ssn;
 241         tid_tx->bar_pending = true;
 242 }
 243
 244 static int ieee80211_tx_radiotap_len(struct ieee80211_tx_info *info)
 245 {
 246         int len = sizeof(struct ieee80211_radiotap_header);
 247
 248         /* IEEE80211_RADIOTAP_RATE rate */
 249         if (info->status.rates[0].idx >= 0 &&
 250             !(info->status.rates[0].flags & (IEEE80211_TX_RC_MCS |
 251                                              IEEE80211_TX_RC_VHT_MCS)))
 252                 len += 2;
 253
 254         /* IEEE80211_RADIOTAP_TX_FLAGS */
 255         len += 2;
 256
 257         /* IEEE80211_RADIOTAP_DATA_RETRIES */
 258         len += 1;
 259
 260         /* IEEE80211_RADIOTAP_MCS
 261          * IEEE80211_RADIOTAP_VHT */
 262         if (info->status.rates[0].idx >= 0) {
 263                 if (info->status.rates[0].flags & IEEE80211_TX_RC_MCS)
 264                         len += 3;
 265                 else if (info->status.rates[0].flags & IEEE80211_TX_RC_VHT_MCS)
 266                         len = ALIGN(len, 2) + 12;
 267         }
 268
 269         return len;
 270 }
 271
 272 static void
 273 ieee80211_add_tx_radiotap_header(struct ieee80211_local *local,
 274                                  struct ieee80211_supported_band *sband,
 275                                  struct sk_buff *skb, int retry_count,
 276                                  int rtap_len, int shift)
 277 {
 278         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 279         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 280         struct ieee80211_radiotap_header *rthdr;
 281         unsigned char *pos;
 282         u16 txflags;
 283
 284         rthdr = (struct ieee80211_radiotap_header *) skb_push(skb, rtap_len);
 285
 286         memset(rthdr, 0, rtap_len);
 287         rthdr->it_len = cpu_to_le16(rtap_len);
 288         rthdr->it_present =
 289                 cpu_to_le32((1 << IEEE80211_RADIOTAP_TX_FLAGS) |
 290                             (1 << IEEE80211_RADIOTAP_DATA_RETRIES));
 291         pos = (unsigned char *)(rthdr + 1);
 292
 293         /*
 294          * XXX: Once radiotap gets the bitmap reset thing the vendor
 295          *      extensions proposal contains, we can actually report
 296          *      the whole set of tries we did.
 297          */
 298
 299         /* IEEE80211_RADIOTAP_RATE */
 300         if (info->status.rates[0].idx >= 0 &&
 301             !(info->status.rates[0].flags & (IEEE80211_TX_RC_MCS |
 302                                              IEEE80211_TX_RC_VHT_MCS))) {
 303                 u16 rate;
 304
 305                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_RATE);
 306                 rate = sband->bitrates[info->status.rates[0].idx].bitrate;
 307                 *pos = DIV_ROUND_UP(rate, 5 * (1 << shift));
 308                 /* padding for tx flags */
 309                 pos += 2;
 310         }
 311
 312         /* IEEE80211_RADIOTAP_TX_FLAGS */
 313         txflags = 0;
 314         if (!(info->flags & IEEE80211_TX_STAT_ACK) &&
 315             !is_multicast_ether_addr(hdr->addr1))
 316                 txflags |= IEEE80211_RADIOTAP_F_TX_FAIL;
 317
 318         if (info->status.rates[0].flags & IEEE80211_TX_RC_USE_CTS_PROTECT)
 319                 txflags |= IEEE80211_RADIOTAP_F_TX_CTS;
 320         if (info->status.rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS)
 321                 txflags |= IEEE80211_RADIOTAP_F_TX_RTS;
 322
 323         put_unaligned_le16(txflags, pos);
 324         pos += 2;
 325
 326         /* IEEE80211_RADIOTAP_DATA_RETRIES */
 327         /* for now report the total retry_count */
 328         *pos = retry_count;
 329         pos++;
 330
 331         if (info->status.rates[0].idx < 0)
 332                 return;
 333
 334         /* IEEE80211_RADIOTAP_MCS
 335          * IEEE80211_RADIOTAP_VHT */
 336         if (info->status.rates[0].flags & IEEE80211_TX_RC_MCS) {
 337                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_MCS);
 338                 pos[0] = IEEE80211_RADIOTAP_MCS_HAVE_MCS |
 339                          IEEE80211_RADIOTAP_MCS_HAVE_GI |
 340                          IEEE80211_RADIOTAP_MCS_HAVE_BW;
 341                 if (info->status.rates[0].flags & IEEE80211_TX_RC_SHORT_GI)
 342                         pos[1] |= IEEE80211_RADIOTAP_MCS_SGI;
 343                 if (info->status.rates[0].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
 344                         pos[1] |= IEEE80211_RADIOTAP_MCS_BW_40;
 345                 if (info->status.rates[0].flags & IEEE80211_TX_RC_GREEN_FIELD)
 346                         pos[1] |= IEEE80211_RADIOTAP_MCS_FMT_GF;
 347                 pos[2] = info->status.rates[0].idx;
 348                 pos += 3;
 349         } else if (info->status.rates[0].flags & IEEE80211_TX_RC_VHT_MCS) {
 350                 u16 known = local->hw.radiotap_vht_details &
 351                         (IEEE80211_RADIOTAP_VHT_KNOWN_GI |
 352                          IEEE80211_RADIOTAP_VHT_KNOWN_BANDWIDTH);
 353
 354                 rthdr->it_present |= cpu_to_le32(1 << IEEE80211_RADIOTAP_VHT);
 355
 356                 /* required alignment from rthdr */
 357                 pos = (u8 *)rthdr + ALIGN(pos - (u8 *)rthdr, 2);
 358
 359                 /* u16 known - IEEE80211_RADIOTAP_VHT_KNOWN_* */
 360                 put_unaligned_le16(known, pos);
 361                 pos += 2;
 362
 363                 /* u8 flags - IEEE80211_RADIOTAP_VHT_FLAG_* */
 364                 if (info->status.rates[0].flags & IEEE80211_TX_RC_SHORT_GI)
 365                         *pos |= IEEE80211_RADIOTAP_VHT_FLAG_SGI;
 366                 pos++;
 367
 368                 /* u8 bandwidth */
 369                 if (info->status.rates[0].flags & IEEE80211_TX_RC_40_MHZ_WIDTH)
 370                         *pos = 1;
 371                 else if (info->status.rates[0].flags & IEEE80211_TX_RC_80_MHZ_WIDTH)
 372                         *pos = 4;
 373                 else if (info->status.rates[0].flags & IEEE80211_TX_RC_160_MHZ_WIDTH)
 374                         *pos = 11;
 375                 else /* IEEE80211_TX_RC_{20_MHZ_WIDTH,FIXME:DUP_DATA} */
 376                         *pos = 0;
 377                 pos++;
 378
 379                 /* u8 mcs_nss[4] */
 380                 *pos = (ieee80211_rate_get_vht_mcs(&info->status.rates[0]) << 4) |
 381                         ieee80211_rate_get_vht_nss(&info->status.rates[0]);
 382                 pos += 4;
 383
 384                 /* u8 coding */
 385                 pos++;
 386                 /* u8 group_id */
 387                 pos++;
 388                 /* u16 partial_aid */
 389                 pos += 2;
 390         }
 391 }
 392
 393 /*
 394  * Handles the tx for TDLS teardown frames.
 395  * If the frame wasn't ACKed by the peer - it will be re-sent through the AP
 396  */
 397 static void ieee80211_tdls_td_tx_handle(struct ieee80211_local *local,
 398                                         struct ieee80211_sub_if_data *sdata,
 399                                         struct sk_buff *skb, u32 flags)
 400 {
 401         struct sk_buff *teardown_skb;
 402         struct sk_buff *orig_teardown_skb;
 403         bool is_teardown = false;
 404
 405         /* Get the teardown data we need and free the lock */
 406         spin_lock(&sdata->u.mgd.teardown_lock);
 407         teardown_skb = sdata->u.mgd.teardown_skb;
 408         orig_teardown_skb = sdata->u.mgd.orig_teardown_skb;
 409         if ((skb == orig_teardown_skb) && teardown_skb) {
 410                 sdata->u.mgd.teardown_skb = NULL;
 411                 sdata->u.mgd.orig_teardown_skb = NULL;
 412                 is_teardown = true;
 413         }
 414         spin_unlock(&sdata->u.mgd.teardown_lock);
 415
 416         if (is_teardown) {
 417                 /* This mechanism relies on being able to get ACKs */
 418                 WARN_ON(!(local->hw.flags &
 419                           IEEE80211_HW_REPORTS_TX_ACK_STATUS));
 420
 421                 /* Check if peer has ACKed */
 422                 if (flags & IEEE80211_TX_STAT_ACK) {
 423                         dev_kfree_skb_any(teardown_skb);
 424                 } else {
 425                         tdls_dbg(sdata,
 426                                  "TDLS Resending teardown through AP\n");
 427
 428                         ieee80211_subif_start_xmit(teardown_skb, skb->dev);
 429                 }
 430         }
 431 }
 432
 433 static void ieee80211_report_used_skb(struct ieee80211_local *local,
 434                                       struct sk_buff *skb, bool dropped)
 435 {
 436         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 437         struct ieee80211_hdr *hdr = (void *)skb->data;
 438         bool acked = info->flags & IEEE80211_TX_STAT_ACK;
 439
 440         if (dropped)
 441                 acked = false;
 442
 443         if (info->flags & (IEEE80211_TX_INTFL_NL80211_FRAME_TX |
 444                            IEEE80211_TX_INTFL_MLME_CONN_TX)) {
 445                 struct ieee80211_sub_if_data *sdata = NULL;
 446                 struct ieee80211_sub_if_data *iter_sdata;
 447                 u64 cookie = (unsigned long)skb;
 448
 449                 rcu_read_lock();
 450
 451                 if (skb->dev) {
 452                         list_for_each_entry_rcu(iter_sdata, &local->interfaces,
 453                                                 list) {
 454                                 if (!iter_sdata->dev)
 455                                         continue;
 456
 457                                 if (skb->dev == iter_sdata->dev) {
 458                                         sdata = iter_sdata;
 459                                         break;
 460                                 }
 461                         }
 462                 } else {
 463                         sdata = rcu_dereference(local->p2p_sdata);
 464                 }
 465
 466                 if (!sdata) {
 467                         skb->dev = NULL;
 468                 } else if (info->flags & IEEE80211_TX_INTFL_MLME_CONN_TX) {
 469                         unsigned int hdr_size =
 470                                 ieee80211_hdrlen(hdr->frame_control);
 471
 472                         /* Check to see if packet is a TDLS teardown packet */
 473                         if (ieee80211_is_data(hdr->frame_control) &&
 474                             (ieee80211_get_tdls_action(skb, hdr_size) ==
 475                              WLAN_TDLS_TEARDOWN))
 476                                 ieee80211_tdls_td_tx_handle(local, sdata, skb,
 477                                                             info->flags);
 478                         else
 479                                 ieee80211_mgd_conn_tx_status(sdata,
 480                                                              hdr->frame_control,
 481                                                              acked);
 482                 } else if (ieee80211_is_nullfunc(hdr->frame_control) ||
 483                            ieee80211_is_qos_nullfunc(hdr->frame_control)) {
 484                         cfg80211_probe_status(sdata->dev, hdr->addr1,
 485                                               cookie, acked, GFP_ATOMIC);
 486                 } else {
 487                         cfg80211_mgmt_tx_status(&sdata->wdev, cookie, skb->data,
 488                                                 skb->len, acked, GFP_ATOMIC);
 489                 }
 490
 491                 rcu_read_unlock();
 492         }
 493
 494         if (unlikely(info->ack_frame_id)) {
 495                 struct sk_buff *ack_skb;
 496                 unsigned long flags;
 497
 498                 spin_lock_irqsave(&local->ack_status_lock, flags);
 499                 ack_skb = idr_find(&local->ack_status_frames,
 500                                    info->ack_frame_id);
 501                 if (ack_skb)
 502                         idr_remove(&local->ack_status_frames,
 503                                    info->ack_frame_id);
 504                 spin_unlock_irqrestore(&local->ack_status_lock, flags);
 505
 506                 if (ack_skb) {
 507                         if (!dropped) {
 508                                 /* consumes ack_skb */
 509                                 skb_complete_wifi_ack(ack_skb, acked);
 510                         } else {
 511                                 dev_kfree_skb_any(ack_skb);
 512                         }
 513                 }
 514         }
 515 }
 516
 517 /*
 518  * Measure Tx frame completion and removal time for Tx latency statistics
 519  * calculation. A single Tx frame latency should be measured from when it
 520  * is entering the Kernel until we receive Tx complete confirmation indication
 521  * and remove the skb.
 522  */
 523 static void ieee80211_tx_latency_end_msrmnt(struct ieee80211_local *local,
 524                                             struct sk_buff *skb,
 525                                             struct sta_info *sta,
 526                                             struct ieee80211_hdr *hdr)
 527 {
 528         u32 msrmnt;
 529         u16 tid;
 530         u8 *qc;
 531         int i, bin_range_count;
 532         u32 *bin_ranges;
 533         __le16 fc;
 534         struct ieee80211_tx_latency_stat *tx_lat;
 535         struct ieee80211_tx_latency_bin_ranges *tx_latency;
 536         ktime_t skb_arv = skb->tstamp;
 537
 538         tx_latency = rcu_dereference(local->tx_latency);
 539
 540         /* assert Tx latency stats are enabled & frame arrived when enabled */
 541         if (!tx_latency || !ktime_to_ns(skb_arv))
 542                 return;
 543
 544         fc = hdr->frame_control;
 545
 546         if (!ieee80211_is_data(fc)) /* make sure it is a data frame */
 547                 return;
 548
 549         /* get frame tid */
 550         if (ieee80211_is_data_qos(hdr->frame_control)) {
 551                 qc = ieee80211_get_qos_ctl(hdr);
 552                 tid = qc[0] & IEEE80211_QOS_CTL_TID_MASK;
 553         } else {
 554                 tid = 0;
 555         }
 556
 557         tx_lat = &sta->tx_lat[tid];
 558
 559         /* Calculate the latency */
 560         msrmnt = ktime_to_ms(ktime_sub(ktime_get(), skb_arv));
 561
 562         if (tx_lat->max < msrmnt) /* update stats */
 563                 tx_lat->max = msrmnt;
 564         tx_lat->counter++;
 565         tx_lat->sum += msrmnt;
 566
 567         if (!tx_lat->bins) /* bins not activated */
 568                 return;
 569
 570         /* count how many Tx frames transmitted with the appropriate latency */
 571         bin_range_count = tx_latency->n_ranges;
 572         bin_ranges = tx_latency->ranges;
 573
 574         for (i = 0; i < bin_range_count; i++) {
 575                 if (msrmnt <= bin_ranges[i]) {
 576                         tx_lat->bins[i]++;
 577                         break;
 578                 }
 579         }
 580         if (i == bin_range_count) /* msrmnt is bigger than the biggest range */
 581                 tx_lat->bins[i]++;
 582 }
 583
 584 /*
 585  * Use a static threshold for now, best value to be determined
 586  * by testing ...
 587  * Should it depend on:
 588  *  - on # of retransmissions
 589  *  - current throughput (higher value for higher tpt)?
 590  */
 591 #define STA_LOST_PKT_THRESHOLD  50
 592 #define STA_LOST_TDLS_PKT_THRESHOLD     10
 593 #define STA_LOST_TDLS_PKT_TIME          (10*HZ) /* 10secs since last ACK */
 594
 595 static void ieee80211_lost_packet(struct sta_info *sta,
 596                                   struct ieee80211_tx_info *info)
 597 {
 598         /* This packet was aggregated but doesn't carry status info */
 599         if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
 600             !(info->flags & IEEE80211_TX_STAT_AMPDU))
 601                 return;
 602
 603         sta->lost_packets++;
 604         if (!sta->sta.tdls && sta->lost_packets < STA_LOST_PKT_THRESHOLD)
 605                 return;
 606
 607         /*
 608          * If we're in TDLS mode, make sure that all STA_LOST_TDLS_PKT_THRESHOLD
 609          * of the last packets were lost, and that no ACK was received in the
 610          * last STA_LOST_TDLS_PKT_TIME ms, before triggering the CQM packet-loss
 611          * mechanism.
 612          */
 613         if (sta->sta.tdls &&
 614             (sta->lost_packets < STA_LOST_TDLS_PKT_THRESHOLD ||
 615              time_before(jiffies,
 616                          sta->last_tdls_pkt_time + STA_LOST_TDLS_PKT_TIME)))
 617                 return;
 618
 619         cfg80211_cqm_pktloss_notify(sta->sdata->dev, sta->sta.addr,
 620                                     sta->lost_packets, GFP_ATOMIC);
 621         sta->lost_packets = 0;
 622 }
 623
 624 static int ieee80211_tx_get_rates(struct ieee80211_hw *hw,
 625                                   struct ieee80211_tx_info *info,
 626                                   int *retry_count)
 627 {
 628         int rates_idx = -1;
 629         int count = -1;
 630         int i;
 631
 632         for (i = 0; i < IEEE80211_TX_MAX_RATES; i++) {
 633                 if ((info->flags & IEEE80211_TX_CTL_AMPDU) &&
 634                     !(info->flags & IEEE80211_TX_STAT_AMPDU)) {
 635                         /* just the first aggr frame carry status info */
 636                         info->status.rates[i].idx = -1;
 637                         info->status.rates[i].count = 0;
 638                         break;
 639                 } else if (info->status.rates[i].idx < 0) {
 640                         break;
 641                 } else if (i >= hw->max_report_rates) {
 642                         /* the HW cannot have attempted that rate */
 643                         info->status.rates[i].idx = -1;
 644                         info->status.rates[i].count = 0;
 645                         break;
 646                 }
 647
 648                 count += info->status.rates[i].count;
 649         }
 650         rates_idx = i - 1;
 651
 652         if (count < 0)
 653                 count = 0;
 654
 655         *retry_count = count;
 656         return rates_idx;
 657 }
 658
 659 void ieee80211_tx_status_noskb(struct ieee80211_hw *hw,
 660                                struct ieee80211_sta *pubsta,
 661                                struct ieee80211_tx_info *info)
 662 {
 663         struct ieee80211_local *local = hw_to_local(hw);
 664         struct ieee80211_supported_band *sband;
 665         int retry_count;
 666         int rates_idx;
 667         bool acked;
 668
 669         rates_idx = ieee80211_tx_get_rates(hw, info, &retry_count);
 670
 671         sband = hw->wiphy->bands[info->band];
 672
 673         acked = !!(info->flags & IEEE80211_TX_STAT_ACK);
 674         if (pubsta) {
 675                 struct sta_info *sta;
 676
 677                 sta = container_of(pubsta, struct sta_info, sta);
 678
 679                 if (!acked)
 680                         sta->tx_retry_failed++;
 681                 sta->tx_retry_count += retry_count;
 682
 683                 if (acked) {
 684                         sta->last_rx = jiffies;
 685
 686                         if (sta->lost_packets)
 687                                 sta->lost_packets = 0;
 688
 689                         /* Track when last TDLS packet was ACKed */
 690                         if (test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH))
 691                                 sta->last_tdls_pkt_time = jiffies;
 692                 } else {
 693                         ieee80211_lost_packet(sta, info);
 694                 }
 695
 696                 rate_control_tx_status_noskb(local, sband, sta, info);
 697         }
 698
 699         if (acked) {
 700                     local->dot11TransmittedFrameCount++;
 701                     if (!pubsta)
 702                             local->dot11MulticastTransmittedFrameCount++;
 703                     if (retry_count > 0)
 704                             local->dot11RetryCount++;
 705                     if (retry_count > 1)
 706                             local->dot11MultipleRetryCount++;
 707         } else {
 708                 local->dot11FailedCount++;
 709         }
 710 }
 711 EXPORT_SYMBOL(ieee80211_tx_status_noskb);
 712
 713 void ieee80211_tx_status(struct ieee80211_hw *hw, struct sk_buff *skb)
 714 {
 715         struct sk_buff *skb2;
 716         struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) skb->data;
 717         struct ieee80211_local *local = hw_to_local(hw);
 718         struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 719         __le16 fc;
 720         struct ieee80211_supported_band *sband;
 721         struct ieee80211_sub_if_data *sdata;
 722         struct net_device *prev_dev = NULL;
 723         struct sta_info *sta, *tmp;
 724         int retry_count;
 725         int rates_idx;
 726         bool send_to_cooked;
 727         bool acked;
 728         struct ieee80211_bar *bar;
 729         int rtap_len;
 730         int shift = 0;
 731
 732         rates_idx = ieee80211_tx_get_rates(hw, info, &retry_count);
 733
 734         rcu_read_lock();
 735
 736         sband = local->hw.wiphy->bands[info->band];
 737         fc = hdr->frame_control;
 738
 739         for_each_sta_info(local, hdr->addr1, sta, tmp) {
 740                 /* skip wrong virtual interface */
 741                 if (!ether_addr_equal(hdr->addr2, sta->sdata->vif.addr))
 742                         continue;
 743
 744                 shift = ieee80211_vif_get_shift(&sta->sdata->vif);
 745
 746                 if (info->flags & IEEE80211_TX_STATUS_EOSP)
 747                         clear_sta_flag(sta, WLAN_STA_SP);
 748
 749                 acked = !!(info->flags & IEEE80211_TX_STAT_ACK);
 750                 if (!acked && test_sta_flag(sta, WLAN_STA_PS_STA)) {
 751                         /*
 752                          * The STA is in power save mode, so assume
 753                          * that this TX packet failed because of that.
 754                          */
 755                         ieee80211_handle_filtered_frame(local, sta, skb);
 756                         rcu_read_unlock();
 757                         return;
 758                 }
 759
 760                 /* mesh Peer Service Period support */
 761                 if (ieee80211_vif_is_mesh(&sta->sdata->vif) &&
 762                     ieee80211_is_data_qos(fc))
 763                         ieee80211_mpsp_trigger_process(
 764                                         ieee80211_get_qos_ctl(hdr),
 765                                         sta, true, acked);
 766
 767                 if ((local->hw.flags & IEEE80211_HW_HAS_RATE_CONTROL) &&
 768                     (ieee80211_is_data(hdr->frame_control)) &&
 769                     (rates_idx != -1))
 770                         sta->last_tx_rate = info->status.rates[rates_idx];
 771
 772                 if ((info->flags & IEEE80211_TX_STAT_AMPDU_NO_BACK) &&
 773                     (ieee80211_is_data_qos(fc))) {
 774                         u16 tid, ssn;
 775                         u8 *qc;
 776
 777                         qc = ieee80211_get_qos_ctl(hdr);
 778                         tid = qc[0] & 0xf;
 779                         ssn = ((le16_to_cpu(hdr->seq_ctrl) + 0x10)
 780                                                 & IEEE80211_SCTL_SEQ);
 781                         ieee80211_send_bar(&sta->sdata->vif, hdr->addr1,
 782                                            tid, ssn);
 783                 }
 784
 785                 if (!acked && ieee80211_is_back_req(fc)) {
 786                         u16 tid, control;
 787
 788                         /*
 789                          * BAR failed, store the last SSN and retry sending
 790                          * the BAR when the next unicast transmission on the
 791                          * same TID succeeds.
 792                          */
 793                         bar = (struct ieee80211_bar *) skb->data;
 794                         control = le16_to_cpu(bar->control);
 795                         if (!(control & IEEE80211_BAR_CTRL_MULTI_TID)) {
 796                                 u16 ssn = le16_to_cpu(bar->start_seq_num);
 797
 798                                 tid = (control &
 799                                        IEEE80211_BAR_CTRL_TID_INFO_MASK) >>
 800                                       IEEE80211_BAR_CTRL_TID_INFO_SHIFT;
 801
 802                                 ieee80211_set_bar_pending(sta, tid, ssn);
 803                         }
 804                 }
 805
 806                 if (info->flags & IEEE80211_TX_STAT_TX_FILTERED) {
 807                         ieee80211_handle_filtered_frame(local, sta, skb);
 808                         rcu_read_unlock();
 809                         return;
 810                 } else {
 811                         if (!acked)
 812                                 sta->tx_retry_failed++;
 813                         sta->tx_retry_count += retry_count;
 814                 }
 815
 816                 rate_control_tx_status(local, sband, sta, skb);
 817                 if (ieee80211_vif_is_mesh(&sta->sdata->vif))
 818                         ieee80211s_update_metric(local, sta, skb);
 819
 820                 if (!(info->flags & IEEE80211_TX_CTL_INJECTED) && acked)
 821                         ieee80211_frame_acked(sta, skb);
 822
 823                 if ((sta->sdata->vif.type == NL80211_IFTYPE_STATION) &&
 824                     (local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS))
 825                         ieee80211_sta_tx_notify(sta->sdata, (void *) skb->data,
 826                                                 acked, info->status.tx_time);
 827
 828                 if (local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS) {
 829                         if (info->flags & IEEE80211_TX_STAT_ACK) {
 830                                 if (sta->lost_packets)
 831                                         sta->lost_packets = 0;
 832
 833                                 /* Track when last TDLS packet was ACKed */
 834                                 if (test_sta_flag(sta, WLAN_STA_TDLS_PEER_AUTH))
 835                                         sta->last_tdls_pkt_time = jiffies;
 836                         } else {
 837                                 ieee80211_lost_packet(sta, info);
 838                         }
 839                 }
 840
 841                 if (acked)
 842                         sta->last_ack_signal = info->status.ack_signal;
 843
 844                 /*
 845                  * Measure frame removal for tx latency
 846                  * statistics calculation
 847                  */
 848                 ieee80211_tx_latency_end_msrmnt(local, skb, sta, hdr);
 849         }
 850
 851         rcu_read_unlock();
 852
 853         ieee80211_led_tx(local);
 854
 855         /* SNMP counters
 856          * Fragments are passed to low-level drivers as separate skbs, so these
 857          * are actually fragments, not frames. Update frame counters only for
 858          * the first fragment of the frame. */
 859         if (info->flags & IEEE80211_TX_STAT_ACK) {
 860                 if (ieee80211_is_first_frag(hdr->seq_ctrl)) {
 861                         local->dot11TransmittedFrameCount++;
 862                         if (is_multicast_ether_addr(hdr->addr1))
 863                                 local->dot11MulticastTransmittedFrameCount++;
 864                         if (retry_count > 0)
 865                                 local->dot11RetryCount++;
 866                         if (retry_count > 1)
 867                                 local->dot11MultipleRetryCount++;
 868                 }
 869
 870                 /* This counter shall be incremented for an acknowledged MPDU
 871                  * with an individual address in the address 1 field or an MPDU
 872                  * with a multicast address in the address 1 field of type Data
 873                  * or Management. */
 874                 if (!is_multicast_ether_addr(hdr->addr1) ||
 875                     ieee80211_is_data(fc) ||
 876                     ieee80211_is_mgmt(fc))
 877                         local->dot11TransmittedFragmentCount++;
 878         } else {
 879                 if (ieee80211_is_first_frag(hdr->seq_ctrl))
 880                         local->dot11FailedCount++;
 881         }
 882
 883         if (ieee80211_is_nullfunc(fc) && ieee80211_has_pm(fc) &&
 884             (local->hw.flags & IEEE80211_HW_REPORTS_TX_ACK_STATUS) &&
 885             !(info->flags & IEEE80211_TX_CTL_INJECTED) &&
 886             local->ps_sdata && !(local->scanning)) {
 887                 if (info->flags & IEEE80211_TX_STAT_ACK) {
 888                         local->ps_sdata->u.mgd.flags |=
 889                                         IEEE80211_STA_NULLFUNC_ACKED;
 890                 } else
 891                         mod_timer(&local->dynamic_ps_timer, jiffies +
 892                                         msecs_to_jiffies(10));
 893         }
 894
 895         ieee80211_report_used_skb(local, skb, false);
 896
 897         /* this was a transmitted frame, but now we want to reuse it */
 898         skb_orphan(skb);
 899
 900         /* Need to make a copy before skb->cb gets cleared */
 901         send_to_cooked = !!(info->flags & IEEE80211_TX_CTL_INJECTED) ||
 902                          !(ieee80211_is_data(fc));
 903
 904         /*
 905          * This is a bit racy but we can avoid a lot of work
 906          * with this test...
 907          */
 908         if (!local->monitors && (!send_to_cooked || !local->cooked_mntrs)) {
 909                 dev_kfree_skb(skb);
 910                 return;
 911         }
 912
 913         /* send frame to monitor interfaces now */
 914         rtap_len = ieee80211_tx_radiotap_len(info);
 915         if (WARN_ON_ONCE(skb_headroom(skb) < rtap_len)) {
 916                 pr_err("ieee80211_tx_status: headroom too small\n");
 917                 dev_kfree_skb(skb);
 918                 return;
 919         }
 920         ieee80211_add_tx_radiotap_header(local, sband, skb, retry_count,
 921                                          rtap_len, shift);
 922
 923         /* XXX: is this sufficient for BPF? */
 924         skb_set_mac_header(skb, 0);
 925         skb->ip_summed = CHECKSUM_UNNECESSARY;
 926         skb->pkt_type = PACKET_OTHERHOST;
 927         skb->protocol = htons(ETH_P_802_2);
 928         memset(skb->cb, 0, sizeof(skb->cb));
 929
 930         rcu_read_lock();
 931         list_for_each_entry_rcu(sdata, &local->interfaces, list) {
 932                 if (sdata->vif.type == NL80211_IFTYPE_MONITOR) {
 933                         if (!ieee80211_sdata_running(sdata))
 934                                 continue;
 935
 936                         if ((sdata->u.mntr_flags & MONITOR_FLAG_COOK_FRAMES) &&
 937                             !send_to_cooked)
 938                                 continue;
 939
 940                         if (prev_dev) {
 941                                 skb2 = skb_clone(skb, GFP_ATOMIC);
 942                                 if (skb2) {
 943                                         skb2->dev = prev_dev;
 944                                         netif_rx(skb2);
 945                                 }
 946                         }
 947
 948                         prev_dev = sdata->dev;
 949                 }
 950         }
 951         if (prev_dev) {
 952                 skb->dev = prev_dev;
 953                 netif_rx(skb);
 954                 skb = NULL;
 955         }
 956         rcu_read_unlock();
 957         dev_kfree_skb(skb);
 958 }
 959 EXPORT_SYMBOL(ieee80211_tx_status);
 960
 961 void ieee80211_report_low_ack(struct ieee80211_sta *pubsta, u32 num_packets)
 962 {
 963         struct sta_info *sta = container_of(pubsta, struct sta_info, sta);
 964         cfg80211_cqm_pktloss_notify(sta->sdata->dev, sta->sta.addr,
 965                                     num_packets, GFP_ATOMIC);
 966 }
 967 EXPORT_SYMBOL(ieee80211_report_low_ack);
 968
 969 void ieee80211_free_txskb(struct ieee80211_hw *hw, struct sk_buff *skb)
 970 {
 971         struct ieee80211_local *local = hw_to_local(hw);
 972
 973         ieee80211_report_used_skb(local, skb, true);
 974         dev_kfree_skb_any(skb);
 975 }
 976 EXPORT_SYMBOL(ieee80211_free_txskb);
 977
 978 void ieee80211_purge_tx_queue(struct ieee80211_hw *hw,
 979                               struct sk_buff_head *skbs)
 980 {
 981         struct sk_buff *skb;
 982
 983         while ((skb = __skb_dequeue(skbs)))
 984                 ieee80211_free_txskb(hw, skb);
 985 }